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Open up the camera application. Can you tap on the screen and have the camera refocus itself? If so, you have a 3. If not, you have a 2.

Way to be giving out wrong information. Both can do it.

Easiest and most surefire way to check if you have an iPad 3 is to check the model and serial number. In many cases, if you restore from a backup, your computer recognizes your new iPad as an iPad 2. Just an error on iTunes end.
 
When I set up my new iPad on Friday, I did a restore from iCloud from my old iPad 2 backup. In my registered devices on my account, it says my new iPad is an iPad 2, even though it isn't. I think it has to do with whatever device you restored from.
 
Wirelessly posted (Mozilla/5.0 (iPhone; CPU iPhone OS 5_1 like Mac OS X) AppleWebKit/534.46 (KHTML, like Gecko) Version/5.1 Mobile/9B179 Safari/7534.48.3)

If it has voice dictation when connected to wifi, it's a 3rd generation.
 
Ok yeah I checked my numbers.
I have the 3.

I wish they put something a little more distinct to let me know though.
 
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